Huawei NetCol5000-A021HN12D 20020E1 Quick Manual page 12

(1) Tilted gas pipe
6
Welding Pipes
1. Do not remove the valve plug when exhausting nitrogen.
2. During the welding process, charge a little nitrogen into the pipes to avoid impurity caused by
internal oxidation.
3. When welding the pipes connecting the indoor and outdoor units, protect the needle valve and its
tag.
4. During welding, take measures to protect the cables around.
5. No face-down bonding.
6. Avoid poor welding.
7. Do not expose welding positions to the environment for a long time. Seal the welding positions. If
foreign matter exists in a welding position, remove it using absolute alcohol or damp cloth and
wait until the position is dry before welding.
8. When welding pipes, ensure that the pipes are dry. Welding the pipes between the indoor and
outdoor units; then welding the two ends of the pipe to the indoor and outdoor units.
9. Each time a pipe in the middle is welded, shock the welding position to remove the clinker and
charge high-pressure nitrogen into the pipe to remove the foreign matter inside.
Pipe support
(2) Inverted traps
Wall
Pipe
(3) Oil traps
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(4) Tilted liquid pipe